APS (automatic protection switching) is a network level redundancy protocol defined for networks based on Sonet, a popular telecommunications standard. The present invention covers how the APS is implemented on a switch of FORE Systems, Warrendale, Pa., and the interaction between the APS scheduling and the backpressure algorithm between the memory controller and the separator on the switch fabric. The present invention is an efficient technique for implementing redundancy when the fabric and port redundancies are not tied together.